Today: Although these countries have declared their political independence from European powers, many of them are still virtually economic colonies of Western powers such as the United States. The Shell Petroleum Development Company (SPDC), for example, derives almost 14 percent of its production from Nigeria, which is dependent on oil for 80 percent of government revenue. However, Nigeria's dependence on Western money for its oil has also contributed to corruption, environmental degradation, and social unrest from tribes such as the Ogoni, who claim Shell's operations are polluting their land.